1. Field of the Invention
This invention relates to a process for providing one or more superheated liquid streams to a vessel by use of heating devices. As used herein, the words “heating device” is meant to include a heat exchanger or a calandria and such words can be used interchangeably. Also, as used herein the word “vessel” or “process vessel” or “chemical process vessel” is meant to include a tower, column (for one example a distillation column), flash drum, vaporizer, or any process equipment that requires a heated liquid stream and such words can be used interchangeably.
2. Description of Related Art
When a liquid process stream is heated with a heating device, with time the process stream can foul the heating device. This requires that the heating device be periodically shut down or taken out of service so that it can be manually cleaned or serviced, meaning that the chemical process associated with heated liquid process stream must also be stopped. However, it is desirable to have a chemical process that continuously provides a heated liquid process stream, one that allows the liquid stream to be switched from a first heating device to a second heating device without having to shut down the entire chemical process.
Providing such a continuous process when the process is superheating a liquid stream has additional challenges, for if the superheated liquid flashes uncontrollably it can damage process equipment. What is needed, therefore, is a continuous process for providing at least one heated liquid stream to a vessel while switching from a first heating device to a second heating device while maintaining the temperature and pressure of the stream to the vessel below a flash point of the liquid, while also maintaining the total amount of superheated liquid provided to the vessel within a desired range necessary for continuous vessel operation without stopping the chemical process or creating other process upsets.